Thermostatically controlled valve



April 25, 1939, L. F. WHITNEY 2,155,880.

-- THERMOSTATICALLY CONTROLLED VALVE Filed July 20, 1937 &

Patented Apr. 25, 1939 2,155,880 THERMOSTATICALLY comonmn vALvn Lyman F. Whitney, Cambridge, Mass, assignor, by mesne assignments, to Stator Corporation,

a corporation of Rhode Island I Application'July 20, 1937, Serial No. 154,538

0 of the snap-disk type.

7 Claims.

burners and more particularly to such a device which is automatically operable to interrupt the supply of fuel to a burner such as a gas burner, should the flame become extinguished.

Heretofore thermostatic devices having an abrupt or snap action have been employed'to shut 011. a gas controlling valve to interrupt the flow of gas to a burner. Such devices are often It has proven diflicult, however, to arrange such devices to operate satisfactorily, if the amount of gas normally being supplied to the burner varies widely and the size and shape of the flame consequently varies considerably. Devices of this character have generally been provided with heat conductors extending into the neighborhood of the flame. If, however, the flame became very small, there was a possibility that the device would act to close the controlling valve although the flame had not been extinguished, thus the supply of heat to the apparatus being warmed was needlessly. interrupted and unnecessary attention upon the part of the user of the device was required. 0n the other hand, if the flame became very large and flared outwardly from the burner jet, such a heat conductor might be subject to rapid deterioration and would in any case tend to absorb a substantial amount of heat from the flame, thus cooling the latter and somewhat impairing the efficiency of the burner.-

It is an object of the present invention to provide a heat conductor associated with an abrupt acting thermostatic device so that the conductor tends to maintain'a more or less constant spacing from the flame of the gas burner despite variations in the size of that flame. To this end I prefer to provide a heat conductor in the form of a bimetallic element which is distortable in re-' sponse to temperature changes so that the element may tend to distort away from a hot, relatively large flame and may tend to move inwardly toward a small flame. Preferably one of the metallic portions of such an element may be integral with a retaining ring which is associated This invention relates to safety devices for Fig. 3 is a central sectional view of such a blank in its partially formed state;

Fig. 4 is a side elevation of a burner assembly with which my safety device may be combined showing the condition of the parts when there is a relatively large flame issuing from the burner, parts being shown in section and in dotted lines; and

Fig. 5 is a similar view 'but showing the device when only a relatively small flame is issuing from the burner.

.In accordance with the present invention, an abruptly acting thermostatic element may be argas pipe, and a heat conductor is arranged effectively to conduct heat to the thermostatic element whether the flame which issues from the gas burner supplied by the fuel line is relatively large or small.

Such a device may comprise a valve casing I with an inlet passage 2 and an outlet passage 3, a valve 4 being engageable with a suitable seat between these passages thus to prevent the flow of gas or the like when closed. The valve 4 is provided with a spindle 4" which is connected to the intermediate part of a bimetallic disk 5. This disk may be formed of two component disks welded or otherwise secured together, materials such as iron'or brass which have diiierent coefiicients of expansion being employed, for example, for this purpose.

. The disk 5 is normally somewhat dished so that the component part having the high coeflicient' of expansion is on the concave side, i. e., toward the valve 4. When the temperature of the disk is raised substantially, the disk therefore tends to flatten and suddenly snaps so that it is dished in the opposite direction, thus opening the valve. When the temperature of the disk thereafter is substantially reduced, the disk will snap back to its normal shape, thus closing the valve.

- The edge of the disk 4 engages a cup-like memher 1 which is held against the valve casing I by a retaining nut 8, and a cap member 10 overlies the edge of the disk, while a spacing washer i2 is disposed between the flanged edge of the cup member 1 and the corresponding edge of the .cap member l0.

. ranged to control a valve in a fuel line, such as a A suitable retaining ring I4 is disposed in clamping position about the flange of the cap member and the cup I. This ring may be conmetrically disposed part i4" having an enlarged end I spaced from the adjoining portion of the ring by a nominal clearance. When the ring is partially formed, it may have the shape shown in Fig. 3, being provided with a continuous annular flange aflording a cylindrical surface concentric with the axis of the ring. Thereafter the edge of this flange may be formed over the marginal portion of the cup member I, as shown in Fig. 1, and the part It may be bent outwardly at a substantial angle to the plane of the remainder oi the ring. Thus the member ll provides part of a suitable heat conducting element l6. This element may, however, be bimetallic, including not only the part M but also a metallic strip ii, the parts N and I5 having quite different coemcients of thermal expansion.

As shown, for example, the ring I4 and its integral extension M may be formed of metal having a relatively high coeflicient of expansion such, for example, as brass, while the strip i5 may be formed of a metal having a substantially lower coeflicient of expansion such, for example, as iron. The strip l5 may be secured to the part M by any suitable means, such as brazing, welding or riveting.

In use a device of this character may be associated with a gas burner 20 of any suitable type, the inlet passage 2 being connected to a gas supply line II and the outlet passage 3 communicating with a duct 23 which is connected to the burner 20. When it is desired to start a burner of this type in operation, the

cap portion in of the device may be heated in any suitable way, as by a match, to cause the thermostatic disk to snap into a position wherein its convex portion is toward the valve 4, thus opening the valve and permitting gas to flow to the tip of the burner 20. Thereupon-the heat, from the flame at the burner tip is effective in causing the disk to retain this form and the valve to remain in its open position.

The member i6 is then effective in conducting heat to the ring ll and thence to the disk 5, it being evident that the enlarged portion il of the bimetallic conductor i6 is particularly efiective in absorbing heat radiated from the neighboring flame. Since, however, the heat conductor i6 is bimetallic, and readiw distortable. under heat, this member will tend to distort awayfromtheflameasthesiaeoftheflame' increases, this position of the parts being shown in Fig. 4. when, however, the quantity of gas being supplied to the bumer is materially reduced, the bimetallic element tends to distort to the position indicated in Fig. 5, so that its outer end including the part il= is maintained in proper juxtaposition to the flame and in a position, for example, which might result in direct contact with a large flame were the member It not distortable. It is thus evident that the member 16 is effective in absorbing heat from the flame and conducting the same to the thermostatic disk 5 despite wide variations in the sire of the flame, Accordingly, even when there is only a small flame issuing from the jet II the conductor causes the thermostatic disk 5 tobewarmenoughtoholdthevalve linopen position, while, when there is a comparatively large, flared time, the end of the conductor i8 is moved am irom the flame, so that the metal thereof is not melted away and so that the flame is not substantlalw cooled by direct contact with the conductor.

It is evident, therefore, that the present-inmostat for moving the valve into' and out of' of engagement with the seat, and a heat conductor to conduct heat from an adjoining flame to the thermostat, said conductor being a bimetallic element which will distort away from a flame as the heat of the same increases.

3. A device of the type described comprising a valve casing, a valve movable into engagement with a seat in the casing, and an abruptly acting thermostat for moving the valve into and out of cut with the seat, and a bimetallic heat conductor to conduct heat from an adjoining flame to the thermostat.

4. A device of the class described comprising a valve casing, a valve movable into engagement with a seat in said casing, a thermostatic disk connected to the valve to move the same into and out of engagement with said seat, a retaining ring secured about the periphery of said disk and an integral strip extending from said ring, said strip forming one element of a bimetallic heat conductor-which may be distorted away from a comparatively hot flame and toward a comparatively small flame.

5. A device of the class described comprising a valve casing, a valve movable into engagement with a seat in said casing, a thermostatic disk connected to the valve to move the same info and-out of engagement with the seat, a cuplike member secured to'the valve casing and providing a peripheral flange amarginal surface of the disk, a cap extending over the disk and having an edge portion on the .opposite marginal surface of the disk, a spacing 6 The combination comprising a burner, a

iuelsupplvlinaavalve'casing for receivingtuel from said line, a fuelduct extending from the casingtotheburnena'valveinsaidcasingengageable with a seat therein to prevent the flow of fuel from said line to said duct, a thermostatic disk operatively connected to said valve toward the flame when the same is comparatively small and distorts away from the flame when the same is comparatively large.

'7. The combination comprising a burner. a fuel supply line, a valve casing for receiving fuel from said line, a fuel duct extending trom thecasingtotheburnenavalveinsaidcasinz engageable with a seat therein to prevent the flow of fuel from said line to said duct, a thermostatic disk operatively connected to said valve to cause the same to engage the seat or move away from the same, a retaining ring disposed about said disk, and a heat conductor extending in generally parallel relation to the axis of a flame emitted from said burner, said conductor being a bimetallic element including a part integral with the ring, said conductor distorting toward the flame when the same is comparatively-small and distorting away from the flame when the same is comparatively large.

- LYMAN F. WHITNEY. 

